1. Field of the Invention
The present invention relates to a damper for absorbing moving energy between a pair of members disposed relatively movably with respect to each other so as to damp the relative movement of the pair of members, as desired. More particularly, the present invention concerns a damper for an automobile seat for absorbing the rotational energy of a rear seat of an automobile arranged to be, for example, rotatable (capable of springing up) so as to be able to eliminate such as a shock occurring in the rear seat at the time of its springing up or returning, sudden springing up of the rear seat due to sudden braking when the rear seat is unlocked, and sudden returning of the sprung-up rear seat due to sudden acceleration, as well as an automobile seat having this damper.
2. Description of the Related Art
As dampers, various dampers are known including a friction damper making use of sliding friction, a fluid damper making use of a fluid, a viscous damper making use of a viscous material, and a lead damper making use of lead. However, the friction damper is accompanied by wear in conjunction with friction and undergoes the deterioration of its characteristics over long periods of use. The fluid damper and the viscous damper are bound to become large in size to obtain a large damping force, and require seals for preventing the leakage of the fluid and the viscous material. The lead damper brings about an increase in weight due to lead, and is difficult to be applied to an apparatus which needs to be made lightweight.
In addition, as a damper for a backrest of an automobile seat, one making use of a fluid is known, but such a damper making use of the fluid is bound to become large in size to obtain a large damping force, and requires a large-scale seal for preventing the leakage of the fluid. In particular, in the case of the damper for an automobile seat in which a backrest is arranged to be folded down and the seat is arranged to be subsequently sprung up in order to secure a large accommodation space within the vehicle compartment, it is necessary to damp large rotational energy based on the total load of the backrest and the seat, so that it is difficult for a compact damper merely making use of a fluid to obtain a targeted large damping force.